SDAA040 July   2025 MSPM0C1104

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 PWM Signal Capture Introduction
    2. 1.2 MSPM0C110x Introduction
  5. 2PWM Signal Capture
    1. 2.1 PWM Signal Capture Methods
    2. 2.2 PWM Signal Capture with TIMx CC Block
    3. 2.3 PWM Signal Capture with GPIO Interrupt
    4. 2.4 Comparison of Different PWM Signal Capture Design
  6. 3Software Realization
    1. 3.1 Identifying Rising and Falling Edge
    2. 3.2 Time Order Classification
    3. 3.3 Signal Filter and Result Calculation
  7. 4System Test
    1. 4.1 Test Setup
    2. 4.2 Variable Monitor
    3. 4.3 PWM Signal Capture Resolution Test and Comparison
  8. 5Summary
  9. 6References

4.1 Test Setup

The waveform generator is required to obtain the reference PWM for testing. The waveform generator can also be replaced by another MCU or DSP which can generate the accurate PWM. Connect the PWM signal to PA23 and GND to LP-MSPM0C1104. Connect the LP-MSPM0C1104 to a PC through a micro-USB cable, as shown in Figure 4-1.

The demo code can be downloaded through E2E forum, the forum link is attached in the References section. Add predefined symbols Capture_CC then click Build to debug the PWM signal capture with TIMx CC block, or add predefined symbols Capture_IO then click Build to debug the PWM signal capture with GPIO interrupt. The Timer Clock Prescaler is set to 5 and Desired Timer Period is set to 12ms in the project to capture the 100Hz frequency PWM.

Hardware Setup for Test Figure 4-1 Hardware Setup for Test